Deceleration of a submerged towed vessel



P 1965 TAMIRO 'WATARI 3,208,424

DECELERATION OF A SUBMERGED TOWED VESSEL Filed 001;. 25, 1963 INVENTOR. TAMIRO WATARI ATTOR/VE United States Patent 3,208,424 DECELERATION OF A SUBMERGED TOWED VESSEL Tamiro Watari, Suma-ku, Kobe-shi, Japan, assignor to Continental Oil Company, Ponca City, Okla., a corporation of Delaware Filed Oct. 23, 1963, Ser. No. 318,422 1 Claim. (Cl. 114-235) This invention is concerned with a submersible tow having a towline fixture on the stem and which produces buoyancy when submerged that has a fixed wing on the hull between said fixture and the center of buoyancy. The fixed wing produces downward force in such manner that the vessel can be taken in tow at a substantially constant depth under water. The invention has for its objects the provision of an improved submersible tow which can be towed under water without application of any maneuvering operation, has reduced tow rope resistance and increased towing speed, and which will remain submerged during towing, and is towed at a substantially constant depth regardless of more or less changes in the towing s eed.

The invention will be explained with reference to an embodiment thereof shown in the accompanying drawing, in which the numeral 1 designates the hull of a submersible tow provided with tail planes 2 on the stern and with a fixture 4 for towline 3 on the stem. To the lower portion of the hull, between said fixture 4 and the center of buoyancy B, is attached a fixed wing 5 on which a downward force applies when the vessel is taken in tow. The symbol G indicates the center of gravity.

As the submersible tow of the invention is constructed as hereinbefore described, when it is towed by the towline 3 with the reserve buoyancy F, held as shown, a downward force F acts on said fixed wing 5 and tends to incline the hull 1 forward below the water lever 6. At this time, the hull 1 tends to be inclined forwardly or downwardly by the action of the resultant force of the downward force F at the fixed wing 5 as described, the buoyancy F and upward force F resulting from the tracting force of the towline 3. Said resultant force, however, is brought in equilibrium with the downward force P, which acts on the hull 1 inclined forward in tow, thereby to maintain said hull 1 at a certain angle of inclination and to permit its submersion to and at a predetermined depth under water.

Thus when the hull 1 is towed under water while keeping the forwardly inclined position as described, and when the towing speed is increased and the downward force F against the hull 1 is intensified, the angle of the forward inclination of the hull is lessened. As a result, the angle of incidence of the fixed wing 5 of the hull 1 becomes smaller and the downward force F at the wing 5 less, and the hull 1 regains an equilibrium of said forces by merely changing the depth slightly and the vessel is towed while keeping a poise forwardly inclined at a predetermined angle.

If, on the contrary, the towing speed for said hull 1 is reduced, the downward force F; against the hull 1 decreases and the hull 1 tends to be floated. However, since the angle of forward inclination of the hull 1 increases due to the buoyancy F and the angle of incidence of the fixed wing 5 increases accordingly to intensify the downward force F that works thereon, the angle of forward inclination of the hull 1 further increases also, partly due 31%,424 Patented Sept. 28, 1965 ice to intensified downward force F, against the hull 1, thereby pulling the hull toward the opposite direction. The forces that act on the hull 1 are therefore brought to an equilibrium again, and said hull 1 can be towed while maintaining a certain angle of forward inclination without materially changing the depth under water. In other words, said hull 1 can be taken in tow with no substantial change in the towing depth, though the angle of forward inclination varies with change of the towing speed.

As has been described above, the present invention provides, in a submersible tow equipped with a towline fixture on the fore body of the hull and which develops buoyancy when submerged, a fixed wing between said fixture and the center of buoyancy and which is subjected to a downward force in such manner that the vessel may be towed at a substantially constant depth under water, whereby a downward force against said fixed wing which is either intensified or lessened in proportion to any change in the towing speed, a downward force applied to the hull, the reserve buoyancy of the hull itself and an upward force applied to the fore body of the vessel by the towline maintain their balanced conditions, and give variations to the angle of inclination of said hull in order to keep the tow depth substantially constant, thereby precluding floating of said vessel in accordance with changes in the towing speed, diminishing the tow rope resistance, and also making it possible to increase the towing speed.

The present invention has many additional advantages and features, in that, for example, the presence of a fixed wing as described permits the vessel to be towed at a substantially constant depth under water without any maneuvering thereof, and the structure can be simplified because it dispenses with movable wings, horizontal rudder and other maneuvering means, and the absence of movable parts minimizes the possibility of troubles.

What is claimed is:

A submersible cargo carrying towed vessel which main tains a substantially constant depth of immersion over a range of towing speeds, comprising:

an elongated hull member having a tow connection at the stem and being ballasted to have a predetermined reserve buoyancy; and

a wing fixedly attached below the hull member at a point between the stem and the center of buoyancy of said hull member to maintain the bow of said hull member at an angle of downward inclination,

said wing fixed to have a pitch which is inclined to the horizontal axis of the hull member such that the downward wing-induced force to the hull member, the reserve buoyancy of the hull member, and any upward force applied to the hull stem at the towing connection, maintain a condition of equilibrium over a range of tow speeds.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS 1,266,466 6/61 France.

FERGUS S. MIDDLETON, Primary Examiner. 

